Engineering Commons^™

A Generalisable Bottom-Up Methodology For Deriving A Residential Stock Model From Large Empirical Databases., Ciara Ahern, Brian Norton

Articles

Average reference dwellings representing a predominant housing typology are defined in this work. Specifying such reference buildings is a prerequisite for (i) calculating cost-optimal energy performance requirements for buildings and building elements and (ii) ensuring valid calculations of national building energy consumption. In the EU, an Energy Performance Certificate (EPC) rating is an assessment of the energy consumption of a dwelling. The use of inappropriate default-values for the building envelope thermal transmittance coefficients (U-values) and standardised thermal bridging transmittance coefficients (Y-values) in the production of EPCs leads to an over-estimation of potential energy savings from interventions in the existing dwelling …

Pollution Prevention Via Recovery Of Cerium (Iv) Oxide In Optics Company, Eugene Park, William Gallagher, Sydor Optics, Flint Creek Resources

Articles

Pollution prevention methods were applied at an optics manufacturer in an effort to improve recovery of a valuable polishing component, cerium oxide (ceria), 77% of which was lost to dragout and sewer discharge. Centrifugation and microfiltratiion were evaluated to develop a process that would increase recovery of used ceria, which would then be sent back to the ceria supplier for reclamation and reuse. Full-scale implementation included a high-speed centrifuge that operates continuously with a microfiltration system through recirculation in a single process tank. Sydor Optics has improved ceria recovery from 23% to 48%, saving thousands of dollars annually.

Simulating Cement Hydration Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer

Articles

HYDCEM is a new cement hydration model to simulate volumetric changes and predict phase assemblage, degree of hydration, heat release, compressive strength and chemical shrinkage over time for PC and limestone binders undergoing hydration for any w/c ratio and curing temperatures between 5 and 45 °C. While models should never completely remove experimental analysis, they are an aid to better understand cement hydration and microstructure development by allowing users analyse different binders in a relatively short time. HYDCEM, written in MATLAB®, is aimed at complementing more sophisticated thermodynamic models giving users a reasonable prediction of hydration behaviour over time, using …

The Application Of Evolutionary Algorithms In Multi-Objective Design And Optimization Of Air Cooled Heatsinks, Younis Osama Abdelsalam, Sajad Alimohammadi, Tim Persoons

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Genetic algorithms (GAs) are considered to be one of the main types of evolutionary algorithms (EAs) and are being increasingly used in various engineering design applications. To a large extent, plate-fin heatsinks are used in the thermal management of compact electronic equipment and data centers. The shape optimization of the heatsinks is not rigorously investigated during the design process of high power electronics. Any improvements in the effectiveness of the heatsinks impact the energy consumed by large-scale information communication technology (ICT) facilities including data centers and telecommunication systems and promote a more sustainable use of raw materials. This paper investigates …

Three-Phase Hydrodynamic Simulation And Experimental Validation Of An Upflow Anaerobic Sludge Blanket Reactor, Camila D' Bastiani, Jéferson Luis Alba, Gabriel Tomazzoni Mazzarotto, Severino Rodrigues De Farias Neto, Anthony Reynolds, David Kennedy, Lademir Luiz Beal

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This research focuses on performing multiphase solid/liquid/gas CFD simulations of a UASB reactor in order to obtain a validated model that provides a clearer understanding of the hydrodynamic behaviour of the three phases in UASB reactors. Eulerian–Eulerian, laminar, three-dimensional, multiphase simulations are carried out using Fluent 16.2. The liquid phase velocity and flow profile are validated through PIV experiments. A liquid mean velocity difference of 8.45% is found between the experimental and numerical results, thus validating the CFD model. Shadowgraphy is applied successfully to validate the biogas phase velocity and bubble size. Based on the hydrodynamic analysis results, the reactor …

A Novel Self-Healing System: Towards A Sustainable Porous Asphalt, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen

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Self-healing asphalt, aimed to produce a sustainable asphalt pavement using green technology, has been studied in the past two decades. Technologies including encapsulated rejuvenator and induction heating have been proposed, demonstrated in the laboratory, and gradually evaluated in field application. This paper looks into the synergy effect of the above two technologies, where induction heating serves as the asphalt damage repair mechanism, requiring just 2 min heating time and encapsulated rejuvenator will replenish (rejuvenate) aged asphalt binder and reinstate bitumen’s healing ability. Moreover, the increased temperature from induction heating could in turn accelerate the diffusion process of rejuvenator into aged …

Smart Routing: Towards Proactive Fault Handling Of Software-Defined Networks, Ali Malik, Benjamin Aziz, Mo Adda, Chih-Heng Ke

Articles

In recent years, the emerging paradigm of software-defined networking has become a hot and thriving topic in both the industrial and academic sectors. Software-defined networking offers numerous benefits against legacy networking systems by simplifying the process of network management through reducing the cost of network configurations. Currently, data plane fault management is limited to two mechanisms: proactive and reactive. These fault management and recovery techniques are activated only after a failure occurrence and hence packet loss is highly likely to occur. This is due to convergence time where new network paths will need to be allocated in order to …

A Validation Study For A New Erosion Model To Predict Erosive Airfoil Defouling, Arthur Rudek, David Muckenhaupt, Thomas Zitzmann, Gerald Russ, Barry Duignan

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A new defouling erosion model for Lagrangian particle tracking is used to predict defouling of amor-phous, heterogeneous coatings such as those typically found in aircraft compressors. The main problem description, the mathematical formulation and the underpinning experiment of the model are presented in a previous communication by the authors. In this work, the Ansys CFX implementation of the model is described and an experiment is presented for the validation of the model. Air flows laden with a number of dry-ice particles are observed in an optically accessible stream channel containing a flat plate target. The defouling process of these particles …

Finite Element Simulation Of Head Impacts In Mixed Martial Arts, Stephen Tiernan, Aidan Meagher, David O'Sullivan Dr, Eoin O'Kelly Dr

Articles

This study determined brain stress and strain in an unhelmeted sport and correlated this with concussive injuries. Thirteen MMA athletes were fitted with the MiG2.0 Stanford instrumented mouthguard. The mouthguard records linear acceleration and angular velocity in 6 degrees of freedom. Angular acceleration was calculated by differentiation. All events were video recorded, time stamped and reported impacts confirmed. 298 impacts above 10g were recorded during sparring sessions and 153 impacts in competitive events. The competitive events resulted in five concussions which were diagnosed by a medical doctor. The impact with the highest angular acceleration from each sparring session and competitive …

Concussion And The Severity Of Head Impacts In Mixed Martial Arts, Stephen Tiernan, Aidan Meagher, David O'Sullivan, Eoin O'Keefe, Eoin O'Kelly, Eugene Wallace, Colin Doherty, Mathew Campbell, Yuzhe Liu, August Domel

Articles

Background: Concern about the consequences of head impacts in US football motivated researchers to investigate and develop instrumentation to measure the severity of these impacts. However, the severity of head impacts in unhelmeted sports is largely unknown as miniaturised sensor technology has only recently made it possible to measure these impacts in vivo.

Aim: The objective of this study was to measure the linear and angular head accelerations in impacts in mixed martial arts (MMA), and correlate these with concussive injuries.

Methods: Thirteen MMA fighters were fitted with the Stanford instrumented mouthguard (MiG2.0). The mouthguard records linear acceleration and angular …

Opinion-Mining On Marglish And Devanagari Comments Of Youtube Cookery Channels Using Parametric And Non-Parametric Learning Models, Sonali Shah, Abhishek Kaushik, Shubham Sharma, Janice Shah

Articles

No abstract provided.

Dynamic Blood-Brain Barrier Regulation In Mild Traumatic Brain Injury, Eoin O'Keeffe, Eoin Kelly, Yuzhe Liu, Chiara Giordano, Eugene Wallace, Mark Hynes, Stephen Tiernan, Aidan Meagher, Chris Greene, Stephanie Hughes, Tom Burke, John Kealy, Niamh Doyle, Alison Hay, Michael Farrell, Gerald A. Grant, Alon Friedman, Ronel Veksler, Michael G. Molloy, James F. Meaney, Niall Pender, David Camarillo, Colin P. Doherty, Matthew Campbell

Articles

Whereas the diagnosis of moderate and severe traumatic brain injury (TBI) is readily visible on current medical imaging paradigms (magnetic resonance imaging [MRI] and computed tomography [CT] scanning), a far greater challenge is associated with the diagnosis and subsequent management of mild TBI (mTBI), especially concussion which, by definition, is characterized by a normal CT. To investigate whether the integrity of the blood-brain barrier (BBB) is altered in a high-risk population for concussions, we studied professional mixed martial arts (MMA) fighters and adolescent rugby players. Additionally, we performed the linear regression between the BBB disruption defined by increased gadolinium contrast …

Fabrication Of Dielectric Elastomers With Improved Electromechanical Properties Using Silicone Rubber And Walnut Polyphenols Modified Dielectric Particles, Liang Jiang, Yuhao Wang, Shipeng Wen, Yanfen Zhou, Qingdao University, Stephen Jerrams

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In this work, polyphenolic extract from walnut green husks (denoted as walnut polyphenols), which is an abun-dant agroindustrial residue/waste, was used to modify barium titanate (BT) particles in the preparation of sili-cone rubber (SR) based dielectric elastomer (DE) composites with enhanced electromechanical performance.By employing walnut polyphenols modification, the dispersibility of BT particles in the SR matrix and the com-patibility between BT and SR were greatly improved, which resulted in enhanced mechanical performance ofthe DE composites. Dielectric property measurement showed that DE composites containing walnut polyphenolsmodified BT particles (WNBT) had higher dielectric constants and lower dielectric losses than that of DEs …

Negative Curvature Hollow Core Fiber Based All-Fiber Interferometer And Its Sensing Applications To Temperature And Strain, Dejun Liu, Wei Li, Qiang Wu, Haoyu Zhao, Fengzi Ling, Ke Tian, Changyu Shen, Fangfang Wei, Wei Han, Gerald Farrell, Yuliya Semenova, Pengfei Wang

Articles

Negative curvature hollow core fiber (NCHCF) is a promising candidate for sensing applications; however, research on NCHCF based fiber sensors starts only in the recent two years. In this work, an all-fiber interferometer based on an NCHCF structure is proposed for the first time. The interferometer was fabricated by simple fusion splicing of a short section of an NCHCF between two singlemode fibers (SMFs). Both simulation and experimental results show that multiple modes and modal interferences are excited within the NCHCF structure. Periodic transmission dips with high spectral extinction ratio (up to 30 dB) and wide free spectral range (FSR) …

Nis2 As A Broadband Saturable Absorber For Ultrafast Pulse Lasers, Pengfei Wang, Han Zhang, Yu Yin, Qiuyun Ouyang, Yujin Chen, Elfed Lewis, Gerald Farrell, Masaki Tokurakawa, Sulaiman Wadi Harun, Cong Wang, Shi Li

Articles

Nickel disulfide (NiS2) has recently been found to possess strong nonlinear saturable absorption properties. This feature is highly attractive for nonlinear photonics applications. Ultrafast pulse generation is successfully demonstrated in this article for both Ytterbium- and Erbium-doped fibre lasers using micro-fibre deposited nickel disulfide (NiS2) as a saturable absorber (SA). The fabricated SA device has a modulation depth of 23% at 1.06 μm and 30.8% at 1.55 μm. Stable dissipative soliton operation was achieved at 1064.5 nm with a pulse duration of 11.7 ps and another stable conventional soliton pulse train was also obtained at 1560.2 nm with a pulse …

Intense Mid-Infrared Emission At 3.9 Μm In Ho3+-Doped Zbya Glasses For Potential Use As A Fiber Laser, Haiyan Zhao, Ruicong Wang, Xin Wang, Shijie Jia, Yaxian Fan, Elfed Lewis, Gerald Farrell, Shunbin Wang, Pengfei Wang

Articles

Intense mid-infrared emission at 3.9 µm in Ho3+-doped ZBYA glasses with direct upper laser level (Ho3+ : 5 I5) pumping at a wavelength of 888 nm is reported for the first time, to the best of our knowledge. Spectroscopic parameters were determined using the Judd–Ofelt theory and the measured absorption spectrum. The maximum emission cross section of the Ho3+-doped ZBYA glass is estimated to be 2.7 × 10−21 cm2 at 3906 nm. Additionally, fluorescence spectra and lifetimes of ZBYA glasses with different Ho3+ ion doping concentrations were measured. The results provide theoretical and experimental basis for better selection of rare-earth-doped …

Gender-Related Differences In Flood Risk Perception And Behaviours Among Private Groundwater Users In The Republic Of Ireland, Cillian P. Mcdowell, Luisa Andrade, Eoin O'Neill, Kevin O'Malley, Jean O'Dwyer, Paul Hynds

Articles

Extreme weather events including flooding can have severe personal, infrastructural, and economic consequences, with recent evidence pointing to surface flooding as a pathway for the microbial contamination of private groundwater supplies. There is a pressing need for increasingly focused information and awareness campaigns to highlight the risks posed by extreme weather events and appropriate subsequent post-event actions. To date, little is known about the presence, directionality or magnitude of gender-related differences regarding flood risk awareness and behaviour among private groundwater users, a particularly susceptible sub-population due to an overarching paucity of infrastructural regulation across many regions. The current study investigated …

Irish Construction Cross Border Trade And Brexit: Practitioner Perceptions On The Periphery Of Europe, Tara Brooks, Lloyd Scott, John P. Spillane, Katy Hayward

Articles

The United Kingdom (UK) Brexit vote of June 2016 has created unprecedented uncertainty in the construction industry in Ireland but little research to date has been undertaken on existing construction trading patterns and the potential effects of regulatory divergence and other nontariff barriers in Ireland in this context. In response, this study uses mixed methods to fill this gap in knowledge. The experience of nine construction industry interviewees is probed – five based in Northern Ireland (in the UK) and four from Ireland, which will remain in the EU after the UK leaves. The researchers’ analysis of the qualitative data …

Advancement Of Predictive Modeling Of Zeta Potentials (Ζ) In Metal Oxide Nanoparticles With Correlation Intensity Index (Cii), Andrey A. Toropov, Natalia Sizochenko, Alla P. Toropova, Danuta Leszczynska, Jerzy Leszczynski

Articles

It was expected that index of the ideality of correlation (IIC) and correlation intensity index (CII) could be used as possible tools to improve the predictive power of the quantitative model for zeta potential of nanoparticles. In this paper, we test how the statistical quality of quantitative structure-activity models for zeta potentials (ζ, a common measurement that reflects surface charge and stability of nanomaterial) could be improved with the use of these two indexes. Our hypothesis was tested using the benchmark data set that consists of 87 measurements of zeta potentials in water. We used quasi-SMILES molecular representation to take …

Thermophotovoltaic Systems For Achieving High-Solar-Fraction Hybrid Solar-Biomass Power Generation, Cm Iftekhar Hussain, Aidan Duffy, Brian Norton

Articles

Medium operating temperature hybrid solar-biomass TPV power plant design requires complex integration of multiple high temperature processes with low band-gap TPV cells. A 0.72 eV band-gap GaSb TPV cell has been used in thermophotovoltaic (TPV) systems operating at temperatures above 1400 °C. Low band-gap TPV cells, such as InGaAs (Eg = 0.55 eV) and InAs (Eg = 0.36 eV) could enable a TPV system to operate optimally at temperatures ≈1000 °C. To examine this, two hybrid solar-biomass TPV system configurations are studied using TRNSYS simulation that incorporates a new algorithm for TPV. It is found that in a high solar …

A Preconditioned Lattice Boltzmann Flux Solver For Steady Flows On Unstructured Hexahedral Grids, Brendan Walsh, Fergal Boyle

Articles

The lattice Boltzmann flux solver (LBFS), first introduced by Shu et al. (2014) on structured meshes, allows fluid flow problems to be solved on unstructured meshes discretised by the finite volume method. The solver calculates the macroscopic fluxes at the cell interfaces from a local reconstruction of the lattice Boltzmann solution. In this paper the LBFS is extended to three-dimensional unstructured hexahedral meshes and a preconditioned lattice Boltzmann flux solver (PLBFS) is presented. The PLBFS involves applying the preconditioning technique proposed by Guo (2004) to the LBFS and is achieved by modifying the equilibrium distribution function used to calculate the …

Land-Based Wind Energy Cost Trends In Germany, Denmark, Ireland, Norway, Sweden And The Unitedstates, Aidan Duffy, Maureen Hand, Ryan Wiser, Eric Lantz, Alberto Dalla Riva, Volker Berkhout, Maria Stenkvist, David Weir, Roberto Lacal-Arántegui

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This paper presents work by the International Energy Agency’s Task 26 ‘Cost of Wind Energy’ on technological and cost trends in land-based wind energy in six participating countries (Denmark, Germany, Ireland, Norway, Sweden, United States) and the European Union between 2008 and 2016. Results indicate that there is a general trend towards larger, taller machines with lower specific powers resulting in higher capacity factors, despite small falls in new site wind resources in most countries, while wind project capital costs and project finance costs also fell. This resulted in an average levelized cost of energy (LCOE) fall of 33% for …

Calibration To Mitigate Near-Field Antennas Effects For A Mimo Radar Imaging System, Ha Hoang, Matthias John, Patrick Mcevoy, Max Ammann

Articles

A calibration method for a high-resolution hybrid MIMO turntable radar imaging system is presented. A line of small metal spheres is employed as a test pattern in the calibration process to measure the position shift caused by undesired antenna effects. The unwanted effects in the antenna near-field responses are analysed, modelled and significantly mitigated based on the symmetry and differences in the responses of the MIMO configuration.

The Fabrication And Properties Of Magnetorheological Elastomers Employing Bio-Inspired Dopamine Modified Carbonyl Iron Particles, Yanfen Zhou, Lele Li, Wenyue Li, Shipeng Wen, Liang Jiang, Stephen Jerrams, Jianwei Ma, Shaojuan Chen

Articles

To obtain magnetorheological elastomers (MREs) with improved mechanical properties and exhibiting an enhanced magnetorheological (MR) effect, bio-inspired dopamine modification has been used to improve the functionality at the surface of carbonyl iron (CI) particles. Various techniques including x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to confirm that a polydopamine (PDA) layer of about 27.5 nm had been successfully deposited on the surface of the carbonyl iron particles prior to their inclusion in the MRE composites. The magnetic properties of PDA modified CI particles were shown to be almost the same as those …

Influence Of Graphene Oxide And Carbon Nanotubes On The Fatigue Properties Of Silica/Styrene-Butadiene Rubber Composites Under Uniaxial And Multiaxial Cyclic Loading, Zongchao Xu, Stephen Jerrams, Hao Guo, Yanfen Zhou, Liang Jiang, Yangyang Gao, Liqun Zhang, Li Liu, Shipeng Wen

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The influence of equivalent replacement of silica (SiO2) by carbon nanotubes (CNT) or graphene oxide (GO) on the microstructure, mechanical and fatigue behaviors of SiO2/styrene-butadiene rubber (SBR) composites was investigated. Results showed that the synergistic effect between CNT (or GO) and SiO2 was beneficial for the filler network and improved the mechanical properties of SBR composites. Furthermore, the introduction of CNT (or GO) led to low crack growth rates and the crack propagation tips were easy to deflection. Under multiaxial fatigue conditions, the maximum engineering stress was determined to be a reliable fatigue life predictor for SBR composites.

Enhanced Fatigue And Durability Of Carbon Black/Natural Rubber Composites Reinforced With Graphene Oxide And Carbon Nanotubes, Hao Guo, Stephen Jerrams, Zongchao Xu, Yanfen Shou, Liang Jiang, Liqun Zhang, Li Liu, Shipeng Wen

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Graphene oxide (GO) sheets and carbon nanotubes (CNTs) are of nanometer size and offer large shape factors which are beneficial in reducing crack propagation rates of composites when used in carbon black (CB) reinforced natural rubber (NR), thereby prolonging the service lives of rubber composites. In this research, CNT-CB/NR and GO-CB/NR composites were prepared by partially replacing CB with one-dimensional CNTs and two-dimensional flaky graphene oxide GO, respectively. The results showed that the complex filler dispersion in NR matrices was improved due to the isolation effect between the different fillers. The strain-induced crystallization (SIC) ability of CB/NR was effectively enhanced …

On The Chirp Function, The Chirplet Transform And The Optimal Communication Of Information, Jonathan Blackledge

Articles

—The purpose of this extended paper is to provide a review of the chirp function and the chirplet transform and to investigate the application of chirplet modulation for digital communications, in particular, the transmission of binary strings. The significance of the chirp function in the solution to a range of fundamental problems in physics is revisited to provide a background to the case and to present the context in which the chirp function plays a central role, the material presented being designed to show a variety of problems with solutions and applications that are characterized by a chirp function in …

Anti-Resonance, Inhibited Coupling And Mode Transitionin Depressed Core Fibers, Xiaokang Lian, Gerald Farrell, Qiang Wu, Wei Han, Changyu Shen, Youqiao Ma, Yuliya Semenova

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The depressed core fiber (DCF), consisting of a low-index solid core, a high-index cladding and air surrounding, is in effect a bridge between the conventional step-index fiber and the tube-type hollow-core fiber from the point of view of the index profile. In this paper the dispersion diagram of a DCF is obtained by solving the full-vector eigenvalue equations and analyzed using the theory of anti-resonant and the inhibited coupling mechanisms. While light propagation in tube-type hollow-core fibers is commonly described by the symmetric planar waveguide model, here we propose an asymmetric planar waveguide for the DCFs in an anti-resonant reflecting …

Optimal Sizing Of Energy Storage With Embedded Wind Power Generation, Nicholas Roche, Jane Courtney

Articles

Energy storage technologies are key to increased penetration of renewable energies on the distribution system. Not only do they increase availability of energy, but they contribute to the overall reliability of the system. However, the cost of large-scale storage systems can often be prohibitive, and storage needs to be sized appropriately, both to fill the energy gaps inevitable in renewable energies such as wind and to minimize costs. In this work, a Monte Carlo Simulation is performed to optimally size an energy storage system while minimizing overall system cost. 30 years of historical wind speed data are used to model …

Impact Assessment Of High-Power Domestic Ev Charging Proliferation Of A Distribution Network, Arsalan Zaidi, Keith Sunderland, Michael Conlon

Articles

Transport electrification is becoming the mainstream as a means to improve efficiency, performance, andsustainability of transportation systems. Electrical vehicles (EVs) can help to de-carbonise the environment, but a downside isthe technical issues presented to the low-voltage distribution network. To quantify the stochastic nature of transport-affectedelectrification, probabilistic load flow is employed. Monte Carlo-based simulation is applied to accommodate the probabilisticuncertainties associated with variable EV charging patterns. This study considers high-power charging (up to 11 kW) at thedomestic level while monitoring power quality variations (voltage drop, voltage unbalance factor, voltage sag) standards. Thiswork focuses on the Irish and UK, distribution system operator's–transmission …